AIDS has become epidemic in modern times and the only therapeutics to date which have proven even partially successful are based upon inhibiting AIDS virus replication. One drug which has been approved for treating AIDS, 3'-azido-2',3'-dideoxythymidine (AZT), exhibits anti-AIDS activity primarily through inhibiting the viral enzyme reverse transcriptase. When AZT is administered to patients it is first phosphorylated to the triphosphate form by cellular kinases. The AZT triphosphate then acts as a terminator of the growing viral DNA chain as well as a reverse transcriptase inhibitor.
Other dideoxynucleosides such as 2',3'-dideoxyadenosine and 2',3'-dideoxyinosine also exhibit antiretroviral activity by inhibiting reverse transcriptase. The therapeutic use of these compounds is limited however, by their rapid degradation via hydrolysis of the sugar base linkage. The instant invention therefore comprises isomeric derivatives of 2',3'-dideoxynucleosides exhibiting a more stable nucleoside linkage.